关键词： Antibacterial effect   Citric acid   Microwave fixation   Poly (MAA)-chitosan graft copolymer   Viscose  

摘要： Purpose This study aims to use multi-functional viscose fabric that was facilely developed with with respect to ease and care characteristics, reinforcement effect and antibacterial activity by using novel echo friendly antibacterial finish based on citric acid/sodium hypophosphite and the authors' previously tailor-made poly meth acrylic acid (MAA)-chitosan graft copolymer via alternative microwave curing approach instead of traditional high-temperature cure one. Design/methodology/approach Viscose fabric was paddled twice in the cross-linking formulations containing different concentrations of citric acid, poly (MAA)-chitosan graft copolymer and sodium hypophosphite to 90 % wet pick up and dried at 100 degrees C for 3 min in an electric oven. Then, the treated fabrics were placed on the disk spinner of the microwave oven and cured at different power (100-800 Watt) for various durations (60-180 s). The fabric was then water-rinsed and dried at ambient condition before use. Findings Results revealed that the above echo friendly method for finished viscose fabrics was found to achieve relatively high dry wrinkle recovery angle and maintain the loss in tensile strength within the acceptable range, as well as antibacterial activity against Escherichia coli and Staphylococcus aureus as a gram-negative and gram-positive bacteria, respectively;in addition to durability up to ten washing cycles. Furthermore, scanning electron microscope images, nitrogen content and add on % of the finished fabric confirmed the penetration of grafted chitosan inside the fabric structure. The tentative mechanism for these reactions is advocated. Originality/value The novelty addressed here is undertaken with the advantages of using citric acid as a nonformaldehyde, safe and cheap poly carboxylic acid as a crosslinking agent and sodium hypophosphite as a potential catalyst, in addition to the authors' noncitable multifunctional echo friendly tailor-made poly (MAA)-chitosan graft copolymer for

关键词： 凝聚胺技术   盐水检验法   输血   效果  

摘要： 目的 探讨凝聚胺技术与其他输血技术在临床输血中实施效果.方法 将60例在2019年10月—2020年10月期间进行健康检查的受检者纳入研究,并以随机双盲法将其分成A组与B组各30例.A组应用常规盐水检验法,B组使用凝聚胺技术检验,对比两组检验结果.结果 在两组凝聚细胞检出率对比上A组低于B组;在血液样本检验结果对比上,B组抗体阳性对照聚集强度优于A组;两组数据对比均有统计学意义(P〈0.05).结论 凝聚胺技术应用到临床输血中,具有检验结果准确性高、操作便捷快速的特点,值得被推广与应用.

摘要： The rnlAB toxin-antitoxin operon from Escherichia co/ifunctions as an anti-phage defense system. RnlA was identified as a member of the HEPN (Higher Eukaryotes and Prokaryotes Nucleotide-binding domain) superfamily of ribonucleases. The activity of the toxin RnlA requires tight regulation by the antitoxin RnlB, the mechanism of which remains unknown. Here we show that RnlA exists in an equilibrium between two different homodimer states: an inactive resting state and an active canonical HEPN dimer. Mutants interfering with the transition between states show that canonical HEPN dimerization via the highly conserved RX4-6 H motif is required for activity. The antitoxin RnlB binds the canonical HEPN dimer conformation, inhibiting RnlA by blocking access to its active site. Single-alanine substitutions mutants of the highly conserved R255, E258, R318 and H323 show that these residues are involved in catalysis and substrate binding and locate the catalytic site near the dimer interface of the canonical HEPN dimer rather than in a groove located between the HEPN domain and the preceding TBP-like domain. Overall, these findings elucidate the structural basis of the activity and inhibition of RnlA and highlight the crucial role of conformational heterogeneity in protein function.

关键词： Finite differences   Finite elements   Conformal mapping   Hilbert transform   Richardson extrapolation   Conformal boundary difference method   Electrostatic and magnetostatic fields   Inhomogeneous   dielectric  

摘要： Purpose This paper aims to solve inhomogeneous dielectric problems by matching boundary conditions at the interfaces among homogeneous subdomains. The capabilities of Hilbert transform computations are deeply investigated in the case of limited numbers of samples, and a refined model is presented by means of investigating accuracies in a case study with three subdomains. Design/methodology/approach The accuracies, refined by Richardson extrapolation to zero error, are compared to finite element (FEM) and finite difference methods. The boundary matching procedures can be easily applied to the results of a previous Schwarz-Christoffel (SC) conformal mapping stage in SC + BC procedures, to cope with field singularities or with open boundary problems. Findings The proposed field computations are of general interest both for electrostatic and magnetostatic field analysis and optimization. They can be useful as comparison tools for FEM results or when severe field singularities can impair the accuracies of other methods. Research limitations/implications This static field methodology, of course, can be used to analyse transverse electro magnetic (TEM) or quasi-TEM propagation modes. It is possible that, in some case, these may make a contribution to the analysis of axis symmetrical problems. Originality/value The most relevant result is the possible introduction of SC + BC computations as a standard tool for solving inhomogeneous dielectric field problems.

关键词： Platinum catalyst   Ethanol oxidation   Cerium zirconium oxide   Carbon nanotube   Electrodeposition  

摘要： Electrocatalytic preparation of Pt-based nanocomposites has been investigated for improvement of direct ethanol fuel cells (DEFCs). In this study, new alternative catalysts of Pt-decorated cerium zirconium oxide-modified multiwalled carbon nanotubes (Pt/CeZrO4/MCNT) were successively prepared to improve the activity of the ethanol oxidation reaction (EOR). The prepared CeZrO4 with a face-centered cubic (fcc) structure compatibly dispersed onto MCNT provides abundant active Pt sites for highly active catalysts. The fcc-structured Pt was also satisfactorily decorated onto CeZrO4/MCNT, resulting in highly active Pt. The Ce4+/Ce3+ redox property can promote oxygen vacancies to improve the electrochemical activity for oxidation of carbonaceous species. An increase in roughness and a stabilized catalyst structure can also be produced by inserting Zr4+ into the ceria metal oxide. The prepared Pt/20%CeZrO4/MCNT catalysts present excellent electrochemical active surface area, mass activity, CO tolerance and high electron kinetic transfer with low resistance and high stability over commercial PtRu/C toward EOR. This promising catalyst material could be introduced to enhance the anodic oxidation reaction in DEFCs. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

关键词： Triclosan   Zebrafish   Alternative splicing   CELF2   Neurotoxicity  

摘要： Herein, we demonstrated that triclosan (TCS) induced neurotoxicity mediated by pre-mRNA alternative splicing (AS). TCS exposure resulted in a series of phenotypic malformations, abnormal locomotor behavior, circadian rhythm disorder and inhibited AChE activity. High throughput mRNA sequencing revealed that TCS regulated the AS events of nerve-related genes. Meanwhile, abnormal expression was observed in marker genes related to nerve cell migration, axon guidance and myelination. The expression of mitochondrial apoptosis activator bcl2l11 was significantly increased under TCS exposure. Interestingly, CELF2 as one of the important RNAbinding proteins was closely related to the AS events, and its mRNA and protein expression levels were significantly increased in zebrafish brain under acute or chronic TCS exposure. Functional knock-down and overexpression of celf2 confirmed that TCS led to nervous system injury and developmental defects through the CELF2-mediated AS events of genes (mbpa, mef2d, u2af2b and matn3b). Histopathological injury, phenotypic malformation, abnormal locomotor behavior and changes in neuromarkers all confirmed the biological functions of CELF2 in zebrafish brain. These findings demonstrate that TCS might regulate some of the AS events of nerverelated genes through upregulating the expression of CELF2. Thus, CELF2 may serve as a target for the prevention, diagnosis and treatment of contaminant-induced neurological diseases.

关键词： Sea level rise (SLR)   Digital elevation model (DEM)   Inundation   Time horizon   Multi-scenario  

摘要： The purpose of this paper is to evaluate three temporal mapping approaches to predict Sea Level Rise (SLR) in the Southern Miami-Dade County, Florida, USA. These three temporal approaches provide an alternative to SLR prediction by the common binary method based on Digital Elevation Models (DEMs). The first temporal approach gathers seven theoretical and semi-empirical scenarios of SLR by the end the century in a single map. The second temporal approach is based on the calculation of the time horizon to inundate each cell of the DEM during ordinary high tides. Finally, the third temporal approach maps the minimum average rate of SLR by which a cell will be inundated by the year 2100. These approaches indicate that, in the second half of the 21st century, a large area on the coast of Miami will be inundated due to SLR. A survey conducted with a group of 73 experts concluded that these approaches were more suitable than other classical approaches for mapping SLR in urban areas.

关键词： Additive manufacturing   Carbon electrode   Drug analysis   Electroanalysis   Paracetamol  

摘要： Here, a novel electrically conductive thermoplastic material composed of graphite/acrylonitrile butadiene styrene (G/ABS) is reported for the first time. This material was explored on the production of 3D printing-based electrochemical sensors with enhanced sensitivity using a novel fabrication approach. The developed G/ABS electrodes showed lower charge transfer resistance (157 vs. 3279 U), higher electroactive area (0.61 vs. 0.19 cm2) and peak currents ca. 69% higher when compared with electrodes fabricated using carbon black/polylactic acid (CB/PLA) commercial filament, which has been widely explored in recent literature. Moreover, the G/ABS sensor provided satisfactory repeatability, reproducibility and stability (relative standard deviations (RSDs) were 1.14%, 6.81% and 10.62%, respectively). This improved performance can be attributed to the fabrication protocol developed here, which allows the incorporation of greater amounts of conductive material in the polymeric matrix. The G/ABS electrode also required a simpler and quicker protocol for activation when compared to CB/PLA. As proof of concept, the G/ABS sensor was employed for electroanalytical quantification of paracetamol (PAR) in pharmaceutical products. The linear concentration range was observed from 0.20 to 30 mmol L-1 and the limit of detection achieved was 54 nmol L-1, much lower than several recent studies dealing with the same analyte. The sensitivity of the G/ABS electrode regarding PAR was also far better when compared to CB/PLA sensor (0.50 mA/mmol L-1 vs. 0.12 mA/mmol L-1). Analyses in commercial pill samples showed good accuracy (recoveries ca. 108%) and precision (RSDs < 5%), suggesting great potential for use of this novel conductive thermoplastic in electroanalytical applications based on 3D printing. (c) 2021 Elsevier B.V. All rights reserved.

关键词： Organic farming   Zero Budget Natural Farming   scientific organic farming   organic cluster   sustainability   India  

摘要： This paper envisages the economic viability of two alternative models of organic farming i.e. Zero Budget Natural Farming (ZBNF) and Scientific Organic Farming. In the empirical survey the study considers two clusters based on the two alternative organic models (i.e. a ZBNF model in Purulia district and a scientific organic farming model in Burdwan district) in West Bengal, India. Performance of these models is evaluated by considering three important parameters i.e. cost of cultivation, yield and income. Evidences reveal that the organic farmers under both models have experienced a reduction in per hectare production cost and yield for their crops in the post-conversion period. Evidences also suggest that farmers adopting ZBNF model in Purulia were able to enhance their income, whereas the income reduced significantly for the farmers practicing scientific organic farming in Burdwan. Moreover, a comparative in-depth analysis of performance is carried out between these two alternative models in order to identify the factors that can influence their long-term sustainability. Results indicate that long term sustainability of the organic model is conditioned upon the interplay of agro-climatic conditions and various other socio-economic factors.